GB1583369A - Vehicle seat - Google Patents

Description

PATENT SPECIFICATION

p<l ( 21) Application No 45465/77 ( 22) Filed 1 Nov 1977 \ ( 31) Convention Application No 51/148493 U( 32) Filed 4 Nov 1976 in ( 1en ( 33) Japan (JP)

X ( 44) Complete specification published 28 Jan a 981 I

Wn ( 51) INT CL 3 B 6 ON 1/02 ( 52) Index at Acceptance A 4 J l AX l L 2 A 3 B 2 A 4 J 2 A 5 A 2 A 7 X 1 2 A 8 D 2 2 ASY ( 54) A VEHICLE SEAT ( 71) We, MITSUBISHI JIDOSHA KOGYO KABIU 511 KI IKAISHA, of No 33-8, 5-Chome, Shiba, Minato-Ku, Tokyo, Japan, and KABUSHIIKI KAISHA IMASEN DENKI SEISAKUSHO, of No 1 Aza Kakihata, Inuyama Shi.

Aiclhi Ken, Japan, both Japanese bodies corporate, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:-

This invention relates to a vehicle seat intended to be used as a front seat of an automobile, and more particularly of a two-door automobile.

It is common practice for the front seats of a two-door automobile to be mounted on rails so that, on release of a catch mechanism, operated, for example, by tilting the back of a front seat forwards with respect to its base, the front seat can be slid forwards to make it easier for a back seat passenger to take or leave his seat.

However, known arrangements have entailed the disadvantage that, after a front seat has been slid forwards in this manner, it is a matter of some difficulty, on sliding the front seat back again, to find a convenient position in which to lock the seat by means of the catch mechanism, so that the driver or front seat passenger must resort to considerable re-adjustment of the respective front seat to find a convenient position.

It is an object of the present invention to provide a vehicle seat, suitable for use in the front of a two-door automobile, and by means of which the above noted disadvantage may be avoided, or at least mitigated.

According to the invention there is provided a vehicle seat comprising a base, a back pivotally connected to the base for pivoting about on axis transverse to the base, the base being mounted for longitudinal sliding movement on a support structure including a rail, herein termed a stationary rail, extending longitudinally of the seat base, and adapted to be secured to the floor of a vehicle, the seat base having fixed thereto a longitudinally extending rail, herein termed a sliding rail, which is in longitudinally sliding engagement with the said stationary rail, the stationary rail having, spaced apart at intervals along a longitudinally extending region thereof, a plurality of locating formations engageable by a complementary formation on a locking lever pivotally mounted on the sliding rail, so that in each of a plurality of longitudinal positions of the seat base with respect to the stationary rail said complementary formation can be engaged in a respective said locating formation on the stationary rail to lock the seat base in position on said supporting structure, the locking lever being resiliently biased to urge said complementary formation towards said longitudinally extending region for engagement in a said locating formation, the sliding rail also having pivotally mounted thereon a control lever mechanically connected with the seat back so as to pivot with respect to the sliding rail upon pivoting of the seat back with respect to the seat base, the control lever and the locking lever being mechanically connected so that by tilting the seat back forwards with respect to the seat base and thereby pivoting the control lever accordingly, the locking lever may thereby be caused to pivot against the bias acting thereon to withdraw said complementary formation from said longitudinally extending region and thus from any said locating formation on the stationary rail to allow the seat base and the sliding rail secured thereto to be slid forwards on said stationary rail, the stationary rail having extending therealong a guide member fixed thereto and engageable by a bearing member carried by said control lever, the arrangement being such that said complementary formation on the locking lever can only engage in a said locating formation when the control lever is in a position in which said bearing member is to one side of said guide member or of an imaginary extension thereof in the longitudinal direction, and such that, when the bearing member is in a position intermediate the longitudinal ends of said guide member and is to said one side of said guide member ( 11) 1583369 1 583 369 and the control lever is pivoted in consequence of tilting the seat back forward with respect to the seat base, said bearing member is resiliently deflected by said guide member in passing to the other side of said guide member, whereas when the bearing member is in a position intermediate the longitudinal ends of said guide member and to said other side of said guide member, said bearing io member engages said guide member to prevent pivoting of said control lever back to its position in which the complementary formation on the locking lever can engage a said locating formation when the seat back is tilted backwards, the seat base with the sliding rail fixed thereto being nevertheless slidable backwards on the stationary rail with the bearing member in the last mentioned position, so that the bearing member slides along the guide member until it passes the rear end thereof, thereby permitting the control lever to return to its position in which the complementary formation on the locking lever can engage a said locating formation and thus lock the seat in a predetermined position on said support structure, the mechanical connection between the locking lever and the control lever permitting manual operation of the locking lever to disengage said complementary formation from said locating formation for adjustment of the position of the seat base on said supporting structure without displacement of said control lever such as to move said bearing member from said one side to said other side of said guide member.

Thus it is possible so to fit a seat according to the invention, as a front seat in a two-door vehicle, that when the seat base and seat back are slid back to a position of use, the seat base is automatically locked in a predetermined position which, if not ideal for a particular front seat passenger or driver, will at least be convenient for the average passenger or driver and will not be too far from an ideal position which can be reached by further adjustment, if necessary, whilst holding the locking lever in its Inoperative position.

An embodiment of this invention is described in detail below with reference to the accompanying drawings, in which: Figure 1 is a schematic side view showing a seat embodying the invention, Figure 2 is a side view showing only the seat rail portion of Figure 1, Figure 3 is a plan view of the portion shown in Figure 2, Figure 4 is a front elevation view of the portion shown in Figure 2, and Figure 5 is a perspective view showing only the seat rail in Figure 1.

Referring to the drawings, a seat base 1 has, fixed at its rear end, on either side, a respective bracket 2 The seat has a back 5 which has at its lower end, on either side, a respective bracket 3 lying against the respective bracket 2 The seat back is pivotally connected with the seat base via a shaft 4 passing through the brackets 2 and 3 so that the seat back can be tilted forwards from the position shown in Figure 1 about a transverse horizontal axis, i e the axis of shaft 4.

A plate 6 which is pivotable on the shaft 4 acts as a lever which pulls a rod 8 when the seat back is tilted forwards to cause a projection 7 fixed to the bracket 3 to bear against plate 6 and thus tilt the plate 6.

A stationary rail 9 fixed to the floor of the automobile engages with a sliding rail fixed to the underside of the seat base 1.

The stationary rail 9 has the form of an upwardly open channel and the inboard side wall of this channel has locating holes 11 formed therein at intervals therealong.

Reference numeral 12 denotes a locking lever that is pivotable about a pin 13 carried on the sliding rail 10 A base part 12 ' of the lever 12 provides a detent 14 for engagement with the locating holes 11 The locking lever 12 has a handle part 16 which extends forwards In the normal position of the seat base and seat back, longitudinal adjustment of the position relative to the stationary rail 9 can be effected simply by longitudinal sliding after pivoting lever 12 manually by means of handle part 16 to disengage detent 14 from the inboard side wall of rail 9 and thus from any locating hole 1 1.

A bell-crank control lever 17 is pivotable about a pin 18 carried by the rail 10, one end 19 of lever 17 engaging pivotably with the rod 8 and the other end of lever 17 carrying a bearing member S engageable with a guide member 26 as discussed below.

The bearing member S is in the form of a shoe and is bent from sheet metal, as are the levers 12 and 17 The end of lever 17 which carries bearing member S is bent to an inverted U-section 19 ' as shown in Figure 5, and receives, between the limbs of the inverted U, a part 20 ' of bearing member S, which part 20 ' is bent to a noninverted U-section The bearing member S is pivotally connected with the lever 17 via a horizontal pivot shaft 21 passed through the side walls providing the limbs of the Ushaped parts 19 ' and 20 '.

In the normal position of the lever 17 in which the detent 14 on lever 12 is engaged in a locating hole 11, the axis of the shaft 21 extends generally longitudinally, nearly parallel with the rails 9, 10 The member S also includes a lug 20 which extends away from shaft 21 and towards rails 9 and 10, the lug 20 providing the part which in operation actually engages member 26.

Reference numeral 30 denotes a spring 1 583 369 fitted around the shaft 21 and which acts on the member S to urge the latter to pivot in a sense such as to move lug 20 upwards and away from the rails 9, 10 Pivotal movement of member S in the latter sense is limited by abutment with lever 17 to the position shown in solid lines in Figure 4 in which lug 20 engages member 26, but the member S may be pivoted to a substantial extent in the opposite sense against the bias of spring 30.

Reference numeral 23 designates a link piece which is formed at one end with an elongate slot 24 through which passes a pin 15 carried by lever 12 so that the link piece is pivotable and longitudinally slidable relative to lever 12 The other end of the link piece 23 is pivotally connected to the control lever 17 via a pin 22 carried by lever 17 Reference numeral 25 denotes a guide plate extending horizontally longitudinally and transversely from the underside of the stationary rail 9 The longitudinal edge of the guide plate 25 bends downward to form the longitudinally extending guide member 26 A coil tension spring 27 is connected between a bracket ' on the side of the sliding rail 10 at its rear end and a bracket 9 ' on the side of the stationary rail 9, so as to urge the sliding rail 10 to slide forwards A coil tension spring 28 is connected between a further bracket on the sliding rail 10 and the locking lever 12, and urges the detent 14 of the locking lever 12 toward the locating holes 11 A coil tension spring 29 connected between the sliding rail 10 and a bent-up lug 23 ' on the link piece 23, urges the control lever 17, via the link piece 23, to pivot in such a sense as to move the member S towards the stationary and sliding rails.

The operation of the seat, when installed as a front seat in a two-door automobile, is as follows Assuming that the seat is initially in a normal position for driving with the rail 10 in the position shown in broken lines in Figure 5 and the operating lever 17 in its normal position, the member S is in the longitudinal position indicated at S' but with the member S in its normal upwardly biased conditon In this initial position, the lug 20 lies under the plate and to one side of an imaginary extension of the member 26, i e to the inner side of member 26 which is nearer the rails 9, When the seat back 5 of the front seat is tilted forward to provide a space for a rear passenger to get in or out, the projection 7 fixed to the metal bracket 3 depresses the plate 6 to cause the latter to pivot about the shaft 4, whereby the rod 8 is pulled backward As a result, as shown in Figure 5, the control lever 17, pulled by the rod 8, rotates about the pin 18 in a direction indicated by the arrow A Consequently, assuming the rail 10 to be in the position, with respect to rail 9, shown in broken lines in Figure 5, the member S on the control lever 17 is displaced, from the position shown in broken lines at S' to a position corresponding to the position indicated at S"but displaced rearwards in the longitudinal direction of the rail, to the appropriate longitudinal position, (which is approximately the same longitudinal position as occupied by the member S where indicated at S') That is to say, the member S swings away from the rails 9, 10 in the direction indicated by the arrow B At the same time, the locking lever 12, which is connected through the link piece 23 to the control lever 17, is caused to pivot against the bias of spring 28 about the pin 13 in the direction indicated by the arrow C, whereby the detent 14 of the locking lever 12 is released from the locating hole 11 in which it was previously engaged On sliding the seat base and seat back together with the sliding rail 10 toward the front of the automobile (i.e in a direction indicated by the arrow M in Figure 5), the member S having the lug moves in a direction indicated by the arrow E, along the longitudinal line D, to the position S"indicated by a double-dot-dash line As a consequence, the space through which rear seat passenger must pass to take or leave the rear seat, not shown, is increased as compared with the case where no longitudinal sliding of the seat base and back takes place.

When the passenger has taken or left the rear seat, the seat base 1 and back 5 are returned to the original position, as described below First, the seat back 5 is tilted into the upright position By the action of the springs 28 and 29, the control lever 17 is caused to pivot about the pin 18 in the direction of the arrow F, in such a manner as to return the rod 8 towards its original position Thereupon, the lug 20 comes in contact with the other, or outer, side of the guide member 26 (as shown in solid lines in Figure 5) In this position, however, the detent 14 of the locking lever 12 cannot engage in any of the locating holes 11, since the lever 12 is restrained by the link piece 23 On sliding the seat base and seat back, together with the sliding rail 10 backwards, the lug 20 slides backwards (in a direction of the arrow N in Figure 5), over the guide member 26, and eventually clears the rear end 26 ' thereof Then, by the action of the springs 28 and 29, the control lever 17 is caused to pivot further about the pin 18 and, simultaneously, the lock lever 12 is caused to pivot about the pin 13 until the levers 17 and 12 have returned to their original positions, travelling in directions indicated by the arrows F and G, respectively Consequently, the detent 14 of the locking 1 583 369 lever 12 automatically engages in the locating hole 11 which corresponds in longitudinal position to that of detent 14 when the member S has cleared the rear end of the guide member 26, whereby the seat base 1 is automatically returned and locked in a predetermined standard position.

However, the seat base and back may be displaced longitudinally, by way of adjustment, from the predetermined standard position referred to, after disengaging the detent 14 from the respective locating hole 11, by pivoting lever 12 by means of the handle 16 as described later, the seat base being locked in the adjusted position by releasing lever 16 to allow detent 14 to engage in the appropriate locating hole.

If the seat has been adjusted in this fashion to a position in which the member S is in a position intermediate the front and rear ends of the member 26, the lug 20 will lie under plate 25 and to the one, or inner, side of member 26 which is nearer the rails 9, When the lug 20 is in such a position when the seat back is tilted forwards, the control lever 17 is pivoted by the rod 8 in the direction A as before, causing the lug 20 to pass transversely under the lower edge of member 26, the member S being resiliently deflected, i e pivoted against the bias of spring 30, to allow the lug 20 to pass under the member 26 The member S is then pivoted by the spring 30 in the reverse direction until arrested by abutment with the lever 17, the lug 20 then lying to the other, or outer side, of member 26 as shown in full lines in Figures 4 and 5 Thereafter, the device operates in the same manner as described before.

If the returned seat cushion 1 in the standard position does not fit the occupant ideally, he can readjust its postion as described below On pivoting the operating lever section 16 of the locking lever 12 in the direction H, the locking lever 12 turns about the pin 13 in the direction C, against the force of the spring 28, and the detent 14 disengages from the locating hole 11 During such operation of lever 12, the pin 15 engaged with the slot 24 slides therealong, and, therefore, the movement of the locking lever 12 is not transmitted to the link piece 23 and the control lever 17 does not rotate By returning the lever handle 16 to its normal position after moving the sliding rail 10, together with the seat back 5 and seat base 1, over the stationary rail 9, to the desired position the seat base and seat back are locked in the adjusted position.

In the above-described embodiment, the coil spring 29 is interposed between the sliding rail 10 and the link piece 23 But it may also be placed between the sliding lever 10 and the control lever 17.

As will be evident from the above description, the pivot (i e, the pin 13) on which the locking lever 12 provided to allow adjustment of the longitudinal position of the seat turns and the pivot (i e the pin 18) on which the control lever 17 memorizing the standard seat setting position turns are separated.

Therefore, the seat described can advantageously be employed in a two-door automobile.

When the front passenger or driver slides the seat base and back backwards, after the rear passenger has taken or left the rear seat, the seat base is locked in a predetermined position and can be adjusted to a different desired position if required By hooking one end of the spring 29 on the link piece 23, jolting of the control lever 17 and the link piece 23 can be prevented Further, the link piece 23 that actuates the lock lever 12 and control lever 17 interlockingly is pin-jointed This arrangement permits a free selection of the fulcrums on which the levers rotate By selecting a suitable lever ratio for each of the levers, therefore, their operating forces can be reduced and a smooth operation of the device results.

Claims (9)

WHAT WE CLAIM IS:

1 A vehicle seat comprising a base, a back pivotally connected to the base for pivoting about an axis transverse to the base, the base being mounted for longitudinal sliding movement on a support structure including a rail, herein termed a stationary rail, extending longitudinally of the seat base, and adapted to be secured to the floor of a vehicle, the seat base having fixed thereto a longitudinally extending rail, herein termed a sliding rail, which is in longitudinally sliding engagement with the said stationary rail, the stationary rail having, spaced apart at intervals along a longitudinally extending region thereof, a plurality of locating formations engageable by a complementary formation on a locking lever pivotally mounted on the sliding rail, so that in each of a plurality of longitudinal positions of the seat base with respect to the stationary rail said complementary formation can be engaged in a respective said locating formation on the stationary rail to lock the seat base in position on said supporting structure, the locking lever being resiliently biased to urge said complementary formation towards said longitudinally extending region for engagement in a said locating formation, the sliding rail also having pivotally mounted thereon a control lever mechanically connected with the seat back so as to pivot with respect to the sliding rail upon pivoting of the seat back with respect to the seat base, the control lever and the locking lever being mechanically connected so that by tilting the seat back forwards with respect to the seat base and thereby pivoting the control lever accordingly, the locking lever may thereby be caused to 1 583 369 pivot against the bias acting thereon to withdraw said complementary formation from said longitudinally extending region and thus from any said locating formation on the stationary rail to allow the seat base and the sliding rail secured thereto to be slid forwards on said stationary rail, the stationary rail having extending therealong a guide member fixed thereto and engageable by a bearing member carried by said control lever, the arrangement being such that said complementary formation on the locking lever can only engage in a said locating formation when the control lever is in a position in which said bearing member is to one side of said guide member or of an imaginary extension thereof in the longitudinal direction, and such that, when the bearing member is in a position intermediate the longitudinal ends of said guide member and is to said one side of said guide member and the control lever is pivoted in consequence of tilting the seat back forward with respect to the seat base, said bearing member is resiliently deflected by said guide member in passing to the other side of said guide member, whereas when the bearing member is in a position intermediate the longitudinal ends of said guide member and to said other side of said guide member, said bearing member engages said guide member to prevent pivoting of said control lever back to its position in which the complementary formation on the locking lever can engage a said locating formation when the seat back is tilted backwards, the seat base with the sliding rail fixed thereto being nevertheless slidable backwards on the stationary rail with the bearing member in the last mentioned position, so that the bearing member slides along the guide member until it passes the rear end thereof, thereby permitting the control lever to return to its position in which the complementary formation on the locking lever can engage a said locating formation and thus lock the seat in a predetermined position on said support structure, the mechanical connection between the locking lever and the control lever permitting manual operation of the locking lever to disengage said complementary formation from said locating formation for adjustment of the position of the seat base on said supporting structure without displacement of said control lever such as to move said bearing member from said one side to said other side of said guide member.

2 A seat according to claim 1 wherein said locating formations are holes in said stationary rail and said complementary formation on the locking lever is a detent engageable in a selected said hole.

3 A seat according to claim 1 or 2 wherein the locking lever and the control lever are connected by means of a link piece pivotally connected at respective ends thereof to the locking lever and the control lever.

4 A seat according to claim 3 wherein the connection of said link piece with one of the two said levers connected therewith is such as to permit a degree of lost motion between the link piece and the respective lever.

A seat according to any preceding claim wherein the locking lever is resiliently biased, to urge said complementary formation towards said locating formations, by a spring acting between the sliding rail and the locking lever.

6 A seat according to claim 5 wherein the control lever is resiliently biased towards its position permitting engagement of the said complementary formation on the locking lever with a said locating formation on the stationary rail.

7 A seat according to claim 6 when dependent on claim 3 wherein the lost motion connection is provided between the link piece and the locking lever and the control lever is resiliently biased by a spring acting between the link piece and the sliding rail.

8 A seat according to any preceding claim wherein said bearing member comprises a shoe pivotally mounted on said control lever so that when the control lever is in its position permitting engagement of said complementary formation on the locking lever with a said locating formation on the stationary rail the pivotal axis of said shoe with respect to the control lever extends generally longitudinally nearly parallel with said rails, said shoe being spring biased to pivot about its pivotal axis towards a limiting position in which further pivoting under the spring bias acting on the shoe is prevented by abutment between the shoe and the control lever, the sense in which said shoe is spring biased being such that when the control lever is in its position permitting engagement of said complementary formation on the locking lever with a said locating formation and the shoe is located intermediate the longitudinal ends of said guide member, the spring bias acting on the shoe acts to urge the shoe towards a position of engagement with said guide member, the shoe being pivotable in the opposite sense, away from such a position of engagement, against the spring bias acting on the shoe, by engagement of the shoe with said guide member, during pivotal movement of the control lever consequent upon tilting the seat back forwards with respect to the seat base, to allow the shoe to pass to the other side of the guide member.

9 A seat according to claim 4 wherein the pivotal connection, permitting a degree of lost motion, between the link piece and the said lever so connected with the link piece comprises a pivot pin carried by the respective lever and extending through an elongate slot formed in the link piece, the lost motion being effected by travel of 1 583 369 the pin along said slot.

A vehicle seat substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

FORRESTER, KETLEY & CO.

Chartered Patent Agents Forrester House, 52 Bounds Green Road, London, NI 1 2 EY.

and also at Rutland House, Scottish Provident Building, 148 Edmund Street, 29 St Vincent Place, BIRMINGHAM B 3 2 LD GLASGOW GI 2 DT.

Agents for the Applicants Printed for Her Majesty's Stationery Office by MULTIPLEX medway ltd, Maidstone, Kent, ME 14 1 JS 1981 Published at the Patent Office, 25 Southampton Buildings, London WC 2 l AY, from which copies may be obtained.